Add required makefiles for new ARM arch variants.

Bug: 364383722
Test: presubmit
Change-Id: I512d2a34e71e677c36b617a9760555c889bfd74b
diff --git a/core/combo/arch/arm64/armv9-3a.mk b/core/combo/arch/arm64/armv9-3a.mk
new file mode 100644
index 0000000..0f2c620
--- /dev/null
+++ b/core/combo/arch/arm64/armv9-3a.mk
@@ -0,0 +1,18 @@
+#
+# Copyright (C) 2025 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# .mk file required to support build for the ARMv9.3-A arch variant.
+# The file just needs to be present, it does not need to contain anything.
diff --git a/core/combo/arch/arm64/armv9-4a.mk b/core/combo/arch/arm64/armv9-4a.mk
new file mode 100644
index 0000000..6ab3bed
--- /dev/null
+++ b/core/combo/arch/arm64/armv9-4a.mk
@@ -0,0 +1,18 @@
+#
+# Copyright (C) 2025 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# .mk file required to support build for the ARMv9.4-A arch variant.
+# The file just needs to be present, it does not need to contain anything.